Grappling arm assembly with latching means

ABSTRACT

An assembly mountable on a dipper stick of a machine having an implement pivotally connected to the dipper stick and means operatively interconnecting the dipper stick and implement for pivoting the implement relative to the dipper stick, generally consisting of an arm member mountable on an underside of the dipper stick for pivotal movement relative to the dipper stick, means for pivoting the arm member between and inoperative position and an operative position cooperable with the implement when the implement is pivoted relative to the dipper stick toward the arm member to grapple objects between the implement and the arm member, and means for detachably latching the arm member in the inoperative position including a first member mountable on one of the dipper sticks and the arm member having at least one recess and a second member mountable on the other of the dipper stick and the arm member having a yieldably biased protuberance receivable in the recess when the arm member is in the inoperative position.

This invention relates to an assembly mountable on a machine forgrappling various objects such as tree trunks, branches, rocks and thelike.

BACKGROUND OF THE INVENTION

In the use of excavating machines typically equipped with a bucket whichmay be curled and uncurled to perform excavating operations, it often isdesirable to grapple and move various articles such as tree trunks,branches, large rocks and the like without materially interrupting theexcavating operation. For this purpose, there has been developed andwidely used in the construction, mining, land clearing and otherindustries, an arm member, commonly referred to as a “thumb,” which ismounted on the underside of the dipper stick of the machine andcooperable with the bucket to grapple objects. Such arm members areeither permanently positioned on the underside of the dipper stick in anextended, operative position or displaceable between an operativeposition cooperative with the bucket or an inoperative position disposedadjacent and detachably secured to the underside of the dipper stick.

In the use of the type of arm member which is displaceable betweenoperative and inoperative positions, it has been found that theconstruction and displacement of such arm members in the prior artrequires an undo interruption of the excavating operation of the machinewhich results in a diminution of productivity. Accordingly, it is theprincipal object of this invention to provide an arm member mountable onthe underside of the dipper stick of a machine which may be easily andquickly displaced between an extended, operative position cooperablewith the bucket of the machine for grappling objects, and a retracted,inoperable position along the underside of the dipper stick, so as notto unduly interrupt the excavating operation of the machine.

SUMMARY OF THE INVENTION

The objects of the present invention are achieved by providing anassembly mountable on the dipper stick of a machine having an implementpivotally connected to the dipper stick and means operativelyinterconnecting the dipper stick and the implement for pivoting theimplement relative to the dipper stick, generally consisting of an armmember mountable on the underside of the stick for pivotal movementrelative to the dipper stick, means for pivoting the arm member betweena retracted, inoperable position and an extended, operative positioncooperable with the implement when the implement is pivoted relative tothe dipper stick toward the implement to grapple objects between theimplement and the arm member, and means for detachably latching the armmember in the inoperative position. Such latching means includes a firstmember mountable on one of the dipper stick and the arm member having atleast one recess and a second member mountable on the other of thedipper stick and the arm member having a yieldably biased protuberancereceivable in the recess when the arm member is in the inoperativeposition. Preferably, the pivoting means for the arm member comprises afluid actuated cylinder assembly which is adapted to be received withinthe envelope of the arm member when the arm member is in the inoperativeposition, and the latching means includes a bracket mounted on theunderside of the dipper stick having a pair of outwardly, yieldablybiased protuberances, and surfaces on the arm member provided withrecesses registrable with such protuberances when the arm member is inthe inoperative position, whereby the protrusions snap-fit into therecesses to displaceably retain the arm member in the inoperativeposition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view of the front end assembly of anexcavating machine, embodying the present invention, illustrating an armmember thereof in an extended operative position;

FIG. 2 is a view similar to the view shown in FIG. 1, illustrating thearm member thereof in a retracted, inoperative position;

FIG. 3 is an enlarged, fragmentary view of the arm member shown in FIGS.1 and 2, shown approaching the retracted, inoperative position andillustrating the latching means therefor;

FIG. 4 is an enlarged view of that portion of FIG. 2 designated by thereference numeral 2;

FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 3;

FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. 4;

FIG. 7 is an enlarged, cross-sectional view taken along line 7-7 in FIG.3; and

FIG. 8 is a partial view of the view shown in FIG. 6 illustrating theretaining component of the latching mechanism in a depressed condition.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT OF THE INVENTION

Referring to FIGS. 1 and 2 of the drawings, there is illustrated thefront end assembly 10 of an excavating machine, equipped with an armassembly 11, embodying the present invention. The front end assemblyincludes a dipper stick 12 pivotally connected to the upper end of aboom 13 of the machine by means of a pivot pin 14, a bucket 15 pivotallyconnected to the free of the dipper stick by means of a pin 16 and anactuating assembly 17. The actuating assembly includes a pair of supportlinks 18, 18 pivotally connected at the lower ends thereof to the sidewalls of the dipper by means of a pair of pins 19, 19, a pair ofactuating links 20, 20 pivotally connected at one set of ends to supportlinks 18 by means of a pin 21, and pivotally connected at the other setof ends thereof to brackets mounted on bucket 15 by means of a set ofpins 22, 22, and a fluid actuated cylinder assembly including a cylindermember 23 pivotally connected to a pair of brackets 24, 24 mounted onthe upper side of the dipper stick by means of a pin 25 and a rod member26 pivotally connected to pin 21. It will be appreciated that uponextension and retraction of rod member 26, bucket 50 will be caused tocurl and uncurl in the conventional manner to operate the machine in aconventional excavating operation.

Arm assembly 11 includes an arm member 30, a fluid actuated cylinder 31and a latching mechanism 32. The arm member consists of a pair oftransversely spaced, elongated plate members 33 and 34 joined togetheradjacent one set of ends by means of a cross plate member 35 and atanother end thereof by a cross plate member 36, and pivotally connectedat the first mention end thereof to a bracket 37 mounted on theunderside of the dipper stick adjacent the free end thereof, by means ofa pivot pin 38. Cross plate member 36 is adapted to engage the cuttingedge 39 of bucket 15 when the bucket is curled to the position as shownin FIG. 1 and arm member 30 is in its extended, operative position alsoas shown in FIG. 1. Plate members 33 and 34 also are provided withjagged edge configurations adjacent the free ends thereof for positivelyengaging an object gripped between the arm member and the bucket duringa grappling operation.

Actuating assembly 31 includes a cylinder member 40 pivotally connectedat the base end thereof to a bracket 41 mounted on the underside of thedipper stick by means of a pin 42, and a rod member 43 connected to aset of brackets 44 mounted on crosspiece member 35, between platemembers 33 and 34, by means of a connecting pin 45. Upon extension andretraction of rod member 43 in the conventional manner, arm member 30may be extended to its operable position as shown in FIG. 1 to cooperatewith bucket 15 in the curled position to grip objects therebetween, andretracted to its inoperative position along the underside of the dipperstick as shown in FIG. 2, to permit the bucket to be curled and uncurledin performing excavating operations. When the arm member is in itsinoperative position along the underside of the dipper stick, cylinderassembly 31 will be disposed within the envelope of the arm member,between plate members 33 and 34 to not only remove the cylinder assemblyfrom the path of the bucket but at least partially shield it fromobjects that could be struck and cause damage thereto.

Latching mechanism 32 is illustrated in detail in FIGS. 3 through 8. Itincludes a first component 50 mounted on the underside of the dipperstick and a second, cooperating component mounted on the free end of thearm member. Latch component 50 includes a pair of brackets 52 and 53mounted on the underside of the dipper stick rearwardly of bracket 41and a transversely disposed latching element 54 supported on suchbrackets. As best illustrated in FIG. 7 each end of latching element 54is provided with a recess 55 having an annular wall in which there ishoused a coil spring 56. Each spring seats on a bottom circular wall ofa recess and engages a button 57 at the opposite end thereof toyieldingly bias the button outwardly as shown in FIG. 7. Each buttonincludes an annular flange portion 57 a and a convex or round portion 57b. Spring 55 bears against the element 57 a and urges the convex portionthrough an opening in an annular element 58 rigidly mounted on an endportion of latching element 54. In the fully extended position under thebiasing action of spring 57 a, convex portion 57 b of each buttonprojects beyond the outer surface of retainer element 58 and isrestrained by engagement of the annular flange portion 57 a engaging theinner surface of retainer element 58.

Referring to FIGS. 5 and 6, a pair of opposed annular elements 60 and 61are rigidly secured to the inner sides of plate members 33 and 34 of thearm member. Such annular elements are disposed coaxially and are pivotalin planes about the axis of connecting pin 38, intersecting the convexportions 57 of latch elements 57. As the arm member is angularlydisplaced from the extended, operative position as shown in FIG. 1 tothe retracted, inoperative position shown in FIG. 2, elements 60 and 61engage and cam the convex portions of buttons 57, causing such buttonsto displace inwardly against the biasing action of the springs and thuspermit such buttons to register with the openings in elements 60 and 61to further permit the buttons to displace outwardly under the biasingaction of the springs and thus cause the arm member to snap-fit ontolatching element 50 in the retracted, inoperative position. When it isdesired to extend the arm member, cylinder assembly 31 is simplyoperated to angularly displace the arm member and correspondingly causeannular elements 60 and 61 to cam buttons 57 inwardly against thebiasing action of the spring to release the arm member from itsretracted, inoperative position.

Under normal excavating operations, the arm member will be retained inthe retracted, inoperative position along the underside of the dipperstick as shown in FIG. 2 with the latching components engaged as shownin FIG. 6. Under such conditions, the boom, dipper stick and bucket maybe operated in the conventional manner to provide an excavatingoperation. With the arm member positioned along the underside of thedipper stick and cylinder assembly 31 nested within the envelope of thearm member, the bucket is free to curl and uncurl as it travels throughits excavating cycle, and cylinder assembly 31 is protected fromstriking any object and thus becoming damaged. When it is desired totemporarily interrupt the excavating operation to remove an object suchas a tree trunk, branches or a large rock, the cylinder assembly 31 isoperated to move the arm member from the retracted, inoperative positionshown in FIG. 2 to the extended, operative position shown in FIG. 1. Thecylinder assembly for the bucket may then be operated to curl the bucketand thus grapple the object sought to be removed. As cylinder assembly31 is operated to angularly displace the arm member, such action willcause annular elements 60 and 61 to cam buttons 57 inwardly against thebiasing action of their associated springs to free the arm member andpermit it to be displaced to its operative position for grappling anitem to be removed. After the particular object has been removed and itis desired to resume the excavating operation, the operator need onlyoperate cylinder assembly 31 to retract the arm member and permit it tobe relatched against the underside of the dipper stick. As the armmember is thus angularly displaced toward the underside of the dipperstick, elements 60 and 61 will again trip buttons 57 to register theopenings therein with the buttons which once more will be urgedoutwardly into such openings to again retain the arm member in itsretracted, inoperative position. As the arm member is thus retracted,cylinder assembly 31 will be received within the arm member to againprotect it from striking any object and becoming damaged.

Because the arm assembly of the present invention may be displacedbetween inoperative and operative positions easily and quickly withouthaving to interrupt the operation of the machine and manually orotherwise manipulate such assembly, the productivity of the machine isnot materially adversely affected. Furthermore, the simplicity of theconstruction and operation of the latching mechanism minimizes the costof manufacturing, assembling and operating the assembly.

From the foregoing detained description it will be evident that thereare a number of changes, adaptations, and modifications of the presentinvention which come within the province of those persons havingordinary skill in the art to which the aforementioned inventionpertains. However, it is intended that all such variations not departingfrom the spirit of the invention be considered as within the scopethereof as limited solely by the appended claims.

1. A grappling assembly for a machine having a boom, comprising: adipper stick pivotally connectable to said boom; an implement pivotallyconnected to said dipper stick; means operatively interconnecting saiddipper stick and said implement for pivoting said implement relative tosaid dipper stick; an arm member connected to an underside of saiddipper stick, pivotal between an operative position cooperable with saidimplement for grappling objects between said arm member and saidimplement when said implement is pivoted toward said arm member, and aninoperative position; means operatively interconnecting said dipperstick and said arm member for pivoting said arm member between saidoperative and inoperative positions; and means for detachably latchingsaid arm member in said operative position including one of said dipperstick and said arm member having at least one transversely extendingrecess and the other of said dipper stick and said arm member having ayieldably biased, transversely displaceable protuberance receivable insaid recess when said arm member is in said inoperative position.
 2. Anassembly according to claim 1 wherein said means for pivoting said armmember is receivable within said arm member when said arm member is insaid inoperative position.
 3. An assembly according to claim 1 whereinsaid means for pivoting said arm member comprises a fluid actuatedcylinder assembly.
 4. An assembly according to claim 1 wherein saidprotuberance comprises a button having a curved outer surface receivablein said recess, and wherein said button is yieldingly biased in aprojecting direction by a spring seated in said one of said dipper stickand said arm member.
 5. An assembly according to claim 1 wherein saidlatching means includes a bracket mounted on the underside of saiddipper stick having a pair of outwardly, yieldingly biasedprotuberances, and surfaces on said arm member provided with recessesregistrable with said protuberances when said arm member is in saidinoperative position, whereby said protuberances snap-fit into saidrecesses to displaceably retain said arm member in said inoperativeposition.
 6. An assembly according to claim 1 wherein the biasing forceexerted on said protuberance is sufficient to yieldingly bias saidprotuberance in said recess registered therewith yet insufficient toretain said protuberance therein upon operation of said means forpivoting said arm member from said inoperative position to saidoperative position.
 7. An assembly according to claim 1 wherein said armmember is provided with a jagged surface engageable with an object beinggrappled.
 8. An assembly mountable on a dipper stick of a machine havingan implement pivotally connected to said dipper stick and meansoperatively interconnecting said dipper stick and said implement forpivoting said implement relative to said dipper stick, comprising: anarm member mountable on an underside of said dipper stick for pivotalmovement relative to said dipper stick; means for pivoting said armmember between an inoperative position and an operative positioncooperable with said implement when said implement is pivoted relativeto said dipper stick toward said arm member to grapple objects betweensaid implement and said arm member; and means for detachably latchingsaid arm member in said inoperative position including a first membermountable on one of said dipper stick and said arm member having atleast one transversely extending recess and a second member mountable onthe other of said dipper stick and said arm member having a yieldablybiased, transversely displaceable protuberance receivable in said recesswhen said arm member is in said inoperative position.
 9. An assemblyaccording to claim 8 wherein said means for pivoting said arm member isreceivable within said arm member when said arm member is in saidinoperative position.
 10. An assembly according to claim 8 wherein saidmeans for pivoting said arm member comprises a fluid actuated cylinderassembly.
 11. An assembly according to claim 8 wherein said protuberancecomprises a button having a curved outer surface receivable in saidrecess, and wherein said button is biased in a projecting direction by aspring seated in said one of said dipper stick and said arm member. 12.An assembly according to claim 8 wherein said latching means includes abracket mountable on the underside of said dipper stick having a pair ofoutwardly, yieldably biased protuberances, and surfaces on said armmember provided with recesses registrable with said protuberances whensaid arm member is in said inoperative position, whereby saidprotuberances snap-fit into said recesses to displaceably retain saidarm member in said inoperative position.
 13. An assembly according toclaim 8 wherein the biasing force exerted on said protuberance issufficient to yieldingly bias said protuberance into said recessregistered therewith yet insufficient to retain said protuberancetherein upon operation of said means for pivoting said arm member fromsaid inoperative position to said operative position.
 14. An assemblyaccording to claim 8 wherein said arm member includes a pair ofelongated, transversely spaced, plate members, and wherein said meansfor pivoting said arm member between an inoperative position and anoperative position is received between said plate members when said armmember is in said inoperative position.
 15. An assembly according toclaim 14 wherein said plate members are provided with jagged surfacesengageable with an object being gripped when said arm member is in saidoperable position.
 16. An assembly according to claim 1 wherein saidmember having said recess includes an element disposed in a planeperpendicular to the pivotal axis of said arm member and including saidprotuberance biased in an extended position, engageable with saidprotuberance in camming relation to cause said protuberance to displaceand then be inserted into said recess when said arm member is angularlydisplaced to said inoperative position.